Crank-shaft lathe.



No. 808,057. PATENTED DEC. 19, 1905- W. H. LUCAS.

CRANK SHAFT LATHE.

APPLICATION FILED DEG.1'I. 1904 3 SHEETS-SHEET 1.

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No. 808,057. PATENTED DEG. 19 1905. W. H. LUCAS.

CRANK SHAFT LATHE.

APPLIGATION FILED DEC. 17, 1904 3 SHEETS-SHEET 2.

No. 808,057. PATENTED DEC. 19, 1905. W. H. LUCAS.

CRANK SHAFT LATHE.

APPLICATION FILED DEO.17,1904

3 SHEETS-SHEET 3.

UNITED STATES PATENT OFFICE.

WVILLIAM H. LUCAS, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO HIMSELF, FRED F. ESPEN. AND JACOB ESPEN, J R, OF PHILADELPHIA,

PENNSYLVANIA.

Specification of Letters Patent.

Patented Dec. 19, 1905.

Application filed December 17, 1904.. sfilifll. NO- 237,269-

To all whom, it may concern:

Be it known that I, I/VILLIAM H. LUCAS, a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented cer tain Improvements in Crank-Shaft Lathes, of which the following is a specification.

The object of my invention is to so construct a lathe for turning crank-shafts or crank-pins that the same can be driven at a higher speed than is possible with crankpinturning lathes as usually constructed. This object I attain in the manner hereinafter set forth, reference being had to the accompanying drawings, in which- Figure 1 is a side view of a crank-shaft or crank-pin turning lathe constructed in accordance with my invention and illustrating the relation of the parts when the shaft is being turned or the sides of the crank-arms are being faced. Fig. 2 is a similar View illus trating the relation of the parts when the crank-pin is being turned and showing in section the fixed and rotatable beds of the machine. Fig. 3 is a front view of the machine. Fig. 4 is a plan view of the rotary table and parts carried thereby, and Fig. 5 is a diagrammatic plan view showing the relation of the tool and tool-holder to the crankshaft during the turning of the crank.

The bed 1 of the machine has thereon or therein suitable bearings for the rotatable horizontal bed-plate 2, which has an annular rack 3 meshing. with a bevel-wheel 4 on a driving-shaft 5, so that it can be freely rotated. At one end of the bed 1 of the machine is a vertical standard 6, and upon the face of the same is vertically guided a slide 7, provided with a horizontal rib 8, upon which is mounted and laterally guided a carriage 9 for the turning-tool 10, the latter being securely confined to the face of the carriage 9 by means of any desired numb er of clamping-b are 11, clamping-bolts 12, and appropriate nuts applied to the latter, the tool-clamping devices being radially beyond the axis of rotation of the bed-plate to at least the extent of the throw of the crank. The rotary bedplate 2 has mounted thereupon so as to be longitudinally adjustable thereon a block 13, thebed-plate having in the present instance longitudinal slots 14 for the reception of the heads of bolts 15, which pass through lugs on the block 13 and have nuts 16 bearmg upon said lugs, so as to effect the secure confinement of the block 13 to the bed-plate in any desired position of adjustment of the block thereon.

Mounted upon the block 13 so as to be laterally adjustable thereon are a pair of clamping-jaws 17, the clamping-bolts 18 for said jaws having heads contained in lateral slots 19 in the block 13 and said bolts having nuts 20 for bearing upon the clamping-jaws, so as tosecurely confine the latter in their various positions of lateral adjustment on the block. Each of the clamping-jaws has a series of clamp-screws 21, whose inner ends bear upon the opposite sides of the crank block :13, formed upon the shaft 12 as shown in Figs. 1, 2, and 3.

Outward movement of the clamping-jaws 17 on the block 13 is limited by contact of said jaws with pins 22, projecting vertically from the upper surface of the block, and lat eral push in either direction upon block 13 is resisted by longitudinal guide bars or ribs 23, formed upon or secured to the upper face of the rotary bed-plate 2, these ribs bearing upon opposite ends of the block 13, and thereby serving to relieve the bolts 15 of lateral strains to which they might otherwise be subjected.

Additional means for securing the crankshaft to the rotary bed-plate 2 is provided by olamp-screws 24 and 25, the screws 24 being carried by ears'26, projecting from the block 13 and the screw 25 passing through a threaded longitudinal opening formed in said blank, said screws 24. and 25 being so located as to engage the shaft y at a point below the crankblock in thereon, as shown in Fig. 3.

In order to relieve the strain upon the over hanging portion of the turningtool 10, a fillmg block or strut 27 is interposed between said overhanging portion of the tool and the face of the carriage 9, as shown in Figs. 1 and 2. The rotary bed-plate has therein an oblong slot 28, extending radially from the center of said bed-plate, and the block 13 has one of its faces recessed, as shown in Fig. 4, so as to conform to the inner portion of said slot, the latter being of a length sufficient to receive the maximum size of crank-block upon which the lathe is intended to operate.

The lathe is intended to turn the journals and crank-pin of a crank-shaft and, if desired, to face the sides of the cranlcarms, the crank-shaft forging, with the solid crankblrgk thereon, being applied to the lathe, as shown in Fig. 1, when it is desired to turn the crank-shaft ournals or face the sides of the crank-arms or being adjusted to the position shown in Fig. 2 when it is desired to cut away the crank-block so as to produce the crankpin. In turning the shaft-journalsthe shaft portions y of the forging are adjusted with their axes in line with the axis of the rotary bed 2 and are properly secured in this position by means of the clamping devices With which the block 13 is provided. When it is desired to cut away the crank-block 90 so as to produce the crank-pin w, the forging is so adjusted in respect to the rotary bed-plate that the axis of the desired crank-pin will be in line with the axis of said rotary bed-plate, the shaft y occupying a position at the outer end of the slot 28 in said bed-plate, as shown in Fig. 2.

One of the main features of my invention is the provision of the lathe with a rotatable horizontal bed-plate to which the crank-shaft can be secured in a vertical position, for by this means the element of gravity is eliminated as a factor in the rotation of the shaft. Hence the provision of heavy counterweights is rendered unnecessary, and the rotary bedplate can be driven at a higher rate of speed than the vertical face-plate of an ordinary crank-pin-turning lathe of the horizontal t pe.

The rotary bed-plate 2 has a depending tubular hub 30, which is slightly tapered externally and is adapted to a similarly-tapered bearing in the stationary bed 1, as shown in Fig. 2, a retaining-ring 81 at the bottom of the hub engaging with a shoulder 32 on the stationary bed to prevent rise of the rotating bed-plate from its bearings. By this means a bearing of large diameter is provided, steadiness of movement of the rotating bedplate is insured, .and the step-bearing for a central spindle usually employed in connection with machines having rotary horizontal bed-plates is rendered unnecessary.

I do not herein claim the process of turning crank-pins, which I have before described, as this forms thesubject of a sepa- 4 rate application filed by me on the 18th day of November, 1905, Serial No. 288,054..

Having thus described my invention, I claim and desire to secure byLettersPatent l. A lathe comprising a frame, a horizontal work-support arranged to rotate about a vertical axis, said support having a slot adapted to admit a crank-shaft, clamping devices connected to the rotary support, and an adjustable tool-slide, substantially as described.

2. A lathe comprising a frame, a horizontal work-support arranged to rotate about a vertical axis, said support havingaslotadapted to admit a crank-shaft, clamping devices connected to the rotary support and arranged to clamp the cranked portion of the shaft when the latter is in vertical position, and an adjustable tool slide, substantially as described.

3. The combination, in a crank-shaft or crank-pin-turning lathe of a rotatable horizontal bed-plate having a slot for the reception and adjustment of the crank-shaft and clamping devices on said bed-plate for engaging the cranked portion of the shaft When 7 said shaft is in a vertical position and also for engaging and imparting rotating move ment to the shaft below the crank, substantially as specified.

4. The combination, in a crank-shaft or crank-pin-turning lathe of a rotatable horizontal bed-plate having a slot for the reception and adjustment of the shaft, and clamping devices on said bed-plate, for engaging the crank-shaft when the latter is in a vertical position, said clamping devices comprising a transversely-adjustable block on the bed-plate, clamping-jaws adjustable transversely on said block, and radially-adjustable clamp-screws for engaging the shaft, substantially as specified.

In testimony whereof I have signedmy name to this specification in the presence of. two subscribing witnesses.

Jos. H. KLEIN. 

